With the development of computer technology and digitalized multi-medium technology, computer devices are widely used in a variety of applications, such as office applications, home entertainments, and business operations. Some of the latest developments successfully combine multi-medium or digital music features in portable computer devices, such as notebook computer and thus allowing general consumers to watch multi-medium films or to listen to digital music with the notebook computers.
However, due to the current trend and requirement from general consumers of miniaturization of the portable electronic devices, playing multi-medium film or digital music with the notebook computers is not the best choice for the consumers and portable multi-medium player and digital music players gradually take place of the notebook computers in playing digital music or multi-medium film. These market available digital playing device comprise a micro storage for storing digital music and multi-medium data that can be retrieved and played by the playing device whereby the general consumers can enjoy the film and music at any time and any place.
The evolution of the digital playing device, however, does not accompany any significant improvement in the operation and control panel, which means the new device is operated with the same old control panel. In the conventional control panel, a number of openings are defined in a casing of the playing device and keys or pushbuttons of the same number extend beyond the openings respectively and are thus accessible by and selectively depressible by the user to operate the playing device. Examples are illustrated in U.S. Designs D469109S and D472245S, in which a casing forms a plurality of openings arranged in a circular configuration each for the extension of a pushbutton to allow the depression by a user.
The conventional control or operation panel requires openings that are formed in advance and are of high precision of location in order to allow for snug extension of the pushbuttons. This does not raise any significant problem in manufacturing for electronic devices of regular sizes, such as household electric appliance or industry electric devices. However, for the miniaturized portable device, extremely severe requirement for high precision must be met in order to effect snug extension of tiny pushbuttons. As a consequence, any defeat in quality control regarding the mechanical dimension of the parts of the playing device will lead to failure of product.
In the previously mentioned US designs, the area surrounded by the pushbuttons is provided with a circular control disk. The disk has an outer rim, which is raised with respect to the casing with a gap existing therebetween. Such a structure forms an obstacle to a user's finger that slides along the surface of the casing for operating the pushbuttons. Such a problem also exists in a variety of portable electronic devices that are currently available in the market.
Even the gap and raised rim that are commonly seen in the operation panel or control panel of the conventional portable electronic devices are made hardly felt by the user, there is still a problem of humidity penetration into the device through the tiny gap to be overcome for the conventional designs. Humidity is one of the major causes that fail the electronic devices.
Thus, the present invention is aimed to solve the above-discussed problems.